Update on the epidemiology of obstructive sleep apnea syndrome in Central Eastern Tunisia over 11 years.

Introduction: obstructive sleep apnea syndrome (OSAS) is the most common sleep-related breathing disorder. Knowledge about OSAS incidence trends could be extremely useful in assessing health needs and implementing preventive measures accordingly. This study aimed at the epidemiological and clinical specificities of OSAS and to give an update on its current chronological trends. Methods: we conducted a retrospective study including all cases of OSAS diagnosed over 11 years, from January 1, 2012, to December 31, 2022, at the Sleep Unit of the Neurophysiology Department of the Sahloul University Hospital, Tunisia. Results: overall, 848 new cases of OSAS were diagnosed. The mean annual number of OSAS cases was 74.8/year. The crude incidence rate (CIR) was 12.3/100000 inhabitants/year, it was significantly increasing over the years (rho=0.7; p=0.01). The median age was 56 (IQR= [48-64]) years, it increased significantly during the study period from 54 years (IQR= [43-63]) in 2012 to 58 years (IQR= [50.5-65]) in 2022 (rho=0.7; p=0.015). The median BMI was 35.5 (IQR= [31.3-40.3]) kg/m2. The median BMI of patients diagnosed with OSAS increased significantly from 34.6 kg/m2 to 38.3 kg/m2 (rho=0.75; p=0.008). This equated to an annual increase in median BMI of 0.41 kg/m2. The median AHI showed a significant upward trend for all patients, rising from 26.30 events/h in 2012 to 34.07 events/h in 2022 (rho=0.68; p=0.02). Conclusion: the CIR of OSAS is related to BMI and age. Thus, we assume that it will continue to increase in the coming years with the rise in obesity and the aging of the population.

Juvenile Dermatomyositis: Diagnosis and Management.

Juvenile dermatomyositis (JDM) is the leading cause of chronic idiopathic inflammatory myopathy of auto-immune origin in children.1 Seven patients with JDM found in the records from 1998-2019 of the Department of Dermatology Farhat Hached Hospital, Sousse, Tunisia. Our study concerned a total of six girls and one boy with a median age at disease onset of 8,16 years.2 The average time before diagnosis was 8,8 months. The onset of the disease was acute in 2 patients. All patients displayed skin manifestations at diagnosis, with proximal muscular weakness in 4 cases. Four patients had elevated muscle enzymes and all of them showed myopathic findings on electromyography. Oral corticosteroids were prescribed in 6 patients, in association with other systemic therapies. Three patients achieved a good outcome while two others relapsed. The two other patients showed corticosteroids resistance with a fatal outcome in one case. This study highlights the diagnostic features and management of juvenile dermatomyositis.

[Predictive factors of polysensitization to contact allergens: study conducted at the Dermato-Allergology Unit of the Farhat Hached University Hospital in Sousse, Tunisia]. / Facteurs prédictifs de la polysensibilisation aux allergènes de contact: étude comparative réalisée à l'Unité de Dermato-Allergologie du CHU Farhat Hached de Sousse, Tunisie.

Introduction: polysensitization is often defined as sensitization to three or more contact allergens. The objectives of our study were to determine the prevalence of polysensitization to allergens patch test and to analyze the factors associated with allergen polysensitization of the European Standard Battery in comparison with cases of oligosensitization. Methods: this is a retrospective descriptive cross-sectional study that included all patients who had undergone patch tests at the Department of Dermato-Allergology of the Department of Occupational Medicine of University Hospital Center Farhat Hached in Sousse spread over 10 years from January 1, 2009 to December 31, 2018. Results: in total, we collected 464 cases of contact dermatitis during the study period. The average age of patients was 38.93 ± 12.52 years with a slight female predominance (52.8% of cases). Among all the patients who consulted during the study period (832 patients), 133 patients had positive reactions to 3 or more allergens 16% of patients. Concerning, the associations of the most frequently noted allergens were those of triplet (chromium, cobalt, and nickel) in 15 patients and triplet (mercaptobenzothiazole, thiuram mix, and IPPD) in 7 cases. The predictive factors of polysensitivity were the personal history of leg ulcers; the site of the lesions in the thorax and the erythematous squamous and dyshidrotic appearance of the lesions. Conclusion: this phenomenon is frequent polysensitization, and close collaboration between dermatologists and occupational physicians to prevent this type of multiple allergies through better management of personal and also professional risk factors.

Rhizobium aouanii sp. nov., efficient nodulating rhizobia isolated from Acacia saligna roots in Tunisia.

Three bacterial strains, 1AS14IT, 1AS12I and 6AS6, isolated from root nodules of Acacia saligna, were characterized using a polyphasic approach. Phylogenetic analysis based on rrs sequences placed all three strains within the Rhizobium leguminosarum complex. Further phylogeny, based on 1 756 bp sequences of four concatenated housekeeping genes (recA, atpD, glnII and gyrB), revealed their distinction from known rhizobia species of the R. leguminosarum complex (Rlc), forming a distinct clade. The closest related species, identified as Rhizobium laguerreae, with a sequence identity of 96.4% based on concatenated recA-atpD-glnII-gyrB sequences. The type strain, 1AS14IT, showed average nucleotide identity (ANI) values of 94.9, 94.3 and 94.1% and DNA-DNA hybridization values of 56.1, 57.4 and 60.0% with the type strains of closest known species: R. laguerreae, Rhizobium acaciae and 'Rhizobium indicum', respectively. Phylogenomic analyses using 81 up-to-date bacteria core genes and the Type (Strain) Genome Server pipeline further supported the uniqueness of strains 1AS14IT, 1AS12I and 6AS6. The relatedness of the novel strains to NCBI unclassified Rhizobium sp. (396 genomes) and metagenome-derived genomes showed ANI values from 76.7 to 94.8% with a species-level cut-off of 96%, suggesting that strains 1AS14I, 1AS12I and 6AS6 are a distinct lineage. Additionally, differentiation of strains 1AS14IT, 1AS12I and 6AS6 from their closest phylogenetic neighbours was achieved using phenotypic, physiological and fatty acid content analyses. Based on the genomic, phenotypic and biochemical data, we propose the establishment of a novel rhizobial species, Rhizobium aouanii sp. nov., with strain 1AS14IT designated as the type strain (=DSM 113914T=LMG 33206T). This study contributes to the understanding of microbial diversity in nitrogen-fixing symbioses, specifically within Acacia saligna ecosystems in Tunisia.

Phytochemical Characterization of Two New Olive Oil Genotypes Growing in Southern Tunisia.

This research can be considered as the first complete survey for the valorization of new olive genotypes cultivated in the South-East of Tunisia as well as their oils. The study aimed to characterize the phytochemical composition of virgin olive oil produced from two olive cultivars, namely Nourgou and Gousalani. The pomological characterization of fruits, the quality criteria and the phytochemical profile were quantified. Additionally, antioxidant activity was evaluated using Ferric reducing antioxidant power (FRAP) and Oxygen radical absorbance capacity (ORAC) tests to also obtain a bioactive characterization of these monovarietal olive oils. The obtained results revealed that the analyzed olive oils samples can be classified into Extra Virgin category (EVOO) according to the regulated physicochemical characteristics. Our findings showed a significant variability in the chemical parameters of the analyzed EVOO likely associated with the genetic potential, mainly for chlorophylls contents (1.37-1.64 mg/kg), in carotenoids pigments (3.97-10.86 mg/kg), in α-tocopherol (175.59-186.87 mg/kg), in sterols (1036.4-1931.4 mg/kg) in oleic acid (65.33-68.73%), in palmitic acid (C16:0) (13.32-17.48%), in linoleic acid (C18:2) (11.06-13.47%). Additionally, the HPLC-MS/MS analysis showed that the two EVOOs analyzed contained appreciable amounts of total polyphenols, ranging from 348.03 up to 516.16 mg/kg, in Nourgou and Gousalani oils, respectively. Regarding the individual phenolic compounds, the EVOO samples were mainly characterized by phenolic alcohols, phenolic acids, secoiridoids, verbascoside, flavonoids and phenolic aldehydes. The prevalent simple phenolics detected were secoiridoids with the dominance of the oleuropein aglycone in Gousalani oil. In addition, findings from in vitro antioxidant assays (FRAP and ORAC) revealed that the two studied oils possessed a powerful antiradical activity and a good reducing power capacity. In conclusion, these new EVOOs exhibited a superior quality compared to other Tunisian varieties, considering their antiradical activity and reducing power capacity.

Prevalence of spine pain among Tunisian children and adolescents and related factors.

BACKGROUND: The prevalence of back and neck pain is common in children and adolescents, and in some series the numbers are alarming. Various risk factors have been identified, although some are controversial. OBJECTIVE: To determine the prevalence of neck and back pain in children and adolescents and to investigate the potential association with various risk factors identified in the literature. METHODS: We established a questionnaire targeting parents of children and adolescents aged between 6 and 18 years old in Tunisia. The recruitment of participants was done online using the Google Forms application. The questionnaire was divided into 2 parts: Part one collected the sociodemographics characteristics of the participants : age, gender, body mass index (BMI), exposure to passive smoking, the practice of a physical activity, puberty status and age at puberty if applicable, type and weight of the schoolbag, mean daily time spent on electronic devices, type of school the child attends (private/public), mode of transport from home to school, parental history of neck and/or back pain (mid or low back pain (LBP)), posture of the sitting position of the child, and finally whether the child reports neck/ back pain. The second part was aimed at parents whose child reported neck and/or back pain. We asked about the weekly frequency of neck/back pain, school absenteeism due to neck/back pain, whether it prevented the child from practicing physical activity and, finally, whether the child had ever seen a doctor/chiropractor/physiotherapist for their neck/back pain. RESULTS: Eighty-eight children (45 females, 43 males) were enrolled. Mean age was 11.9 ± 3.8 years [6-18]. Mean BMI was 18.8 ± 4.2 [15.8-35.5]. Thirty-four (38.6%) were pubescent. Twenty-five (28.4%) children were exposed to passive smoking. Parental history of spine pain was found in 58% of cases. A poor sitting position was noted in n = 49 (55.7%). Mean daily screen time was 88.3 ± 75.56 min [0-360]. Prevalence of spine pain was 44% (n = 39) distributed as follows: neck pain (n = 21, 23.8%), mid back pain (n = 15, 17%), LBP (n = 26, 29.5%), neck, mid back and low back pain (n = 4, 4.5%) Professional help seeking for spine pain in children was reported by 15 participants (25.3%). Among them, 20.3% visited a physician and 5% consulted a chiropractor or physiotherapist. A significant correlation was found between spine pain and age (p = 0.006) and BMI (p = 0.006). A significant association was found between LBP and exposure to passive smoking, puberty status, type of school bag and poor posture. A positive parental history of spine pain was significantly associated with the presence of spine pain in their children with p = 0.053 (neck pain), p = 0.013 (back pain) and p < 0.00 (LBP) respectively. A significant association was found between the presence of spine pain and school absenteeism, participation in sports, consultation with a doctor or physiotherapist/chiropractor (p < 0.0001 respectively). CONCLUSION: The prevalence of spinal pain was frequent in our series. A positive parental history of spinal pain, a bad posture while sitting, passive smoking, use of backpack, higher age and higher BMI were potential associated factors.

New insights on the hydrochemistry, geothermometry, and isotopic characteristics of the hydrothermal groundwater of the SASS basin: case study of the Jérid geothermal field, Southern Tunisia.

Chemical and isotopic indicators were used to recognize the origin of hydrothermal groundwater, to assess the mineralization processes and groundwater quality, to identify the source of solutes and the likely mixing with cold, and elucidate the fluid geothermometry in the Jérid field of Southern Tunisia. The results show that the geothermal groundwater is neutral to slightly alkaline. They are characterized by SO4-Cl-Na-Ca water type. The dissolution of evaporates and pyrite-bearing rocks is the dominant mineralization process. The groundwater quality index indicates that the majority of samples are very hard and belong to poor to unsuitable for drinking classes. Applications and calculations of hydrogeochemical parameters, including SAR, %Na, PI, Kr, and MAR, showed that the majority of samples are unsuitable for agricultural practices. The human health risk was assessed based on hazard quotient and total hazard index through ingestion and dermal contact with iron-rich groundwater. The consumption of CI groundwaters does not present non-carcinogenic risk to adults and children. The δ18 O and δ2H signatures indicate that the geothermal groundwater was recharged by ocean precipitation during cold and wet paleoclimatic periods. The slight enrichment of oxygen-18 and deuterium contents suggests a limited mixing effect between geothermal water and cold groundwater within the same aquifer. This mixing effect is confirmed by the Na-K-Mg and the chloride-enthalpy diagrams. The K-Mg and SiO2 geothermometers provided fairly reliable reservoir temperature values, ranging between 69.6 and 99 °C. Calculated geothermal potential values, varying between 469 and 16987 kWth, which allow several applications such as domestic and agricultural heating.

Tapping into haloalkaliphilic bacteria for sustainable agriculture in treated wastewater: insights into genomic fitness and environmental adaptation.

The increasing salinity and alkalinity of soils pose a global challenge, particularly in arid regions such as Tunisia, where about 50% of lands are sensitive to soil salinization. Anthropogenic activities, including the use of treated wastewater (TWW) for irrigation, exacerbate these issues. Haloalkaliphilic bacteria, adapted to TWW conditions and exhibiting plant-growth promotion (PGP) and biocontrol traits, could offer solutions. In this study, 24 haloalkaliphilic bacterial strains were isolated from rhizosphere sample of olive tree irrigated with TWW for more than 20 years. The bacterial identification using 16S rRNA gene sequencing showed that the haloalkaliphilic isolates, capable of thriving in high salinity and alkaline pH, were primarily affiliated to Bacillota (Oceanobacillus and Staphylococcus). Notably, these strains exhibited biofertilization and enzyme production under both normal and saline conditions. Traits such as phosphate solubilization, and the production of exopolysaccharide, siderophore, ammonia, and hydrogen cyanide were observed. The strains also demonstrated enzymatic activities, including protease, amylase, and esterase. Four selected haloalkaliphilic PGPR strains displayed antifungal activity against Alternaria terricola, with three showing tolerances to heavy metals and pesticides. The strain Oceanobacillus picturea M4W.A2 was selected for genome sequencing. Phylogenomic analyses indicated that the extreme environmental conditions probably influenced the development of specific adaptations in M4W.A2 strain, differentiating it from other Oceanobacillus picturae strains. The presence of the key genes associated with plant growth promotion, osmotic and oxidative stress tolerance, antibiotic and heavy metals resistance hinted the functional capabilities might help the strain M4W.A2 to thrive in TWW-irrigated soils. By demonstrating this connection, we aim to improve our understanding of genomic fitness to stressed environments. Moreover, the identification of gene duplication and horizontal gene transfer events through mobile genetic elements allow the comprehension of these adaptation dynamics. This study reveals that haloalkaliphilc bacteria from TWW-irrigated rhizosphere exhibit plant-growth promotion and biocontrol traits, with genomic adaptations enabling their survival in high salinity and alkaline conditions, offering potential solutions for soil salinization issues.

Marine fungal community composition and diversity across a polluted site in the south Mediterranean coast: the Monastir Bay, Tunisia.

Marine fungi communities play a crucial role in the recycling of nutrients, restoration of biological systems, and the overall functioning of ecosystems. While aquatic fungal communities do react to pollution, there is a significant lack of information regarding the changes in the fungal community's structure, caused by marine pollution. In this study, we aim to address this gap in knowledge by investigating the range and makeup of fungal species present in marine environments in a polluted bay in Tunisia, spanning a biodiversity hotspot (Monastir Bay). Sequence analysis of the internal transcribed spacer region from culturable mycobiome and physicochemical parameters were investigated at seven sites in the bay. A total of 32 fungal taxa were identified at the genus and/or species levels and were assigned to four major groups (Aspergillacae 37.5%, Dothiomyceta 21.87%, Sordariamyceta 28.12%, and Yeasts 12.5%) with a remarkable predominance of Aspergillus genus. Assessment of the Shannon-Wiener diversity index and the Simpson dominance index revealed that the highest species diversity index (0.84) was recorded at the Kheniss site. Our results suggest the existence of diverse fungal communities, can be considered a useful community model for further ecological and evolutionary study of fungi in the bay.

Impulsivity as a predictor of clinical and psychological outcomes in a naturalistic prospective cohort of subjects at ultra-high risk (UHR) for psychosis from Tunisia.

BACKGROUND: Impulsivity is associated with serious detrimental consequences on physical, mental, behavioral and social aspects of health among patients with psychosis. The present prospective 12-month follow-up study aimed to determine the prevalence of highly impulsive individuals among Ultra High Risk (UHR) patients, how impulsivity evolves over the follow-up period, and whether impulsivity impacts clinical, psychological and functional outcomes in this population. METHOD: UHR patients were invited to complete a battery of measurements at three-time points: at baseline, and at 6 and 12 months of follow-up. Impulsivity was assessed using both behavioral (the Wisconsin Card Sorting Test, WCST) and self-report (the Barratt Impulsiveness Scale, BIS-11) measures. RESULTS: Findings showed that at 6 months of follow-up, higher 6-month BIS-11 attentional and motor impulsivity were significantly associated with lower quality of life and greater general psychological distress. In addition, higher baseline BIS-11 motor impulsivity significantly predicted more severe positive psychotic symptoms at 12 months of follow-up. However, WCST scores did not show any significant associations with study variables at the different times of follow-up. CONCLUSION: Interventions targeting impulsivity in UHR individuals could help decrease psychological distress and positive psychotic symptoms' severity, as well as improve quality of life in UHR individuals.

Genome Tunisia Project: paving the way for precision medicine in North Africa.

BACKGROUND: Key discoveries and innovations in the field of human genetics have led to the foundation of molecular and personalized medicine. Here, we present the Genome Tunisia Project, a two-phased initiative (2022-2035) which aims to deliver the reference sequence of the Tunisian Genome and to support the implementation of personalized medicine in Tunisia, a North African country that represents a central hub of population admixture and human migration between African, European, and Asian populations. The main goal of this initiative is to develop a healthcare system capable of incorporating omics data for use in routine medical practice, enabling medical doctors to better prevent, diagnose, and treat patients. METHODS: A multidisciplinary partnership involving Tunisian experts from different institutions has come to discern all requirements that would be of high priority to fulfill the project's goals. One of the most urgent priorities is to determine the reference sequence of the Tunisian Genome. In addition, extensive situation analysis and revision of the education programs, community awareness, appropriate infrastructure including sequencing platforms and biobanking, as well as ethical and regulatory frameworks, have been undertaken towards building sufficient capacity to integrate personalized medicine into the Tunisian healthcare system. RESULTS: In the framework of this project, an ecosystem with all engaged stakeholders has been implemented including healthcare providers, clinicians, researchers, pharmacists, bioinformaticians, industry, policymakers, and advocacy groups. This initiative will also help to reinforce research and innovation capacities in the field of genomics and to strengthen discoverability in the health sector. CONCLUSIONS: Genome Tunisia is the first initiative in North Africa that seeks to demonstrate the major impact that can be achieved by Human Genome Projects in low- and middle-income countries to strengthen research and to improve disease management and treatment outcomes, thereby reducing the social and economic burden on healthcare systems. Sharing this experience within the African scientific community is a chance to turn a major challenge into an opportunity for dissemination and outreach. Additional efforts are now being made to advance personalized medicine in patient care by educating consumers and providers, accelerating research and innovation, and supporting necessary changes in policy and regulation.

Clinical and molecular predictors of survival among atypical parkinsonian syndromes in a North African tertiary referral center.

INTRODUCTION: Atypical Parkinsonian Syndromes(APS) are challenging neurodegenerative disorders due to their heterogeneous phenotypic overlaps.So far,there are no validated biomarkers that can accurately predict disease progression,and survival studies were highly different and contradictory. AIM: To investigate clinical and molecular survival factors among Tunisian APS patients. METHODS: A retrospective study included Tunisian APS-patients.Using clinical and molecular parameters,survival was explored by Kaplan-Meier analysis. RESULTS: We included 409-APS patients divided into 166-DLB,112-PSP,81-MSA and 50-CBS.Survival rate was similar in synucleinopathies, while it differed in tauopathies,being shorter in PSP compared to CBS.Median survival in DLB was different according to gender(p = 0.0048),early parkinsonism and cognitive disorders. Among MSA, prognosis was worse in MSA-C-patients(p = 0.012) and those with stridor(p = 0.0049),oculomotor and neuropsychiatric disorders. For tauopathies, survival was shorter in PSP-RS(p = 0.027),cerebellar phenotype, those with tremor and swallowing problems at onset, early parkinsonism and memory impairment. For CBS,prognosis was worse in patients with tremor,swallowing and cognitive problems.Significant differences were noted in terms of survival across APS non-carriers of APOE-ε4(p < 0.001) as well APS patients carriers of MAPT-H1.PSP patients had lower survival rate according to MAPT haplotype carriage. Moreover, the number of copies had an influence as patients with H1/H2-MAPT profile had better prognosis than those with H1/H1. CONCLUSION: This study determined survival rates in APS subgroups,which were comparable across synucleinopathies but shorter in PSP and longer in CBS.It also characterized demographic,phenotypic,and genetic profiles identifying more aggressive forms within APS subgroups.These findings address clinical gaps,aiding counseling for patients and families and guiding clinical management.Furthermore,they could facilitate patient stratification in clinical trials where mortality is an outcome measure.

First Molecular and Phylogenetic Identification of Toxoplasma Gondii in Sheep Liver Intended for Human Consumption in Northern Tunisia.

The aim of this study was to estimate the molecular infection prevalence of Toxoplasma gondii in sheep liver tissues destined for human consumption. A total number of 224 liver tissues were collected from slaughtered sheep in Sejnane slaughterhouse (Northwest Tunisia). PCR was used to detect T. gondii DNA in liver tissues followed by phylogenetic analysis of amplicons. The phylogenetic tree was then constructed to compare the partial sequences of the ITS1 gene with GenBank sequences.The overall molecular prevalence of T. gondii in sheep livers was 25% (56/224). The highest molecular prevalence of T. gondii was recorded in sheep aged of less than one year old (27.3%; 52/190). Infection prevalence was significantly higher in Noire de Thibar breed (33%; 17/51) compared to other breeds (p = 0.023). There were no differences depicted according to sheep's gender. The T. gondii sequences obtained in the present study (GenBank accession numbers: OR509829 and OR509830) were 98.40-100% homologous to T. gondii sequences published in the GenBank. These results highlight a high level of T. gondii contamination of tissues destined for human consumption. Further studies are needed to improve our knowledge on different genotypes of T. gondii that infect Tunisian sheep population.

Transitioning to Insulin Analogs in Tunisian Children with Type 1 Diabetes: Efficacy and Safety.

INTRODUCTION: there is a lack of research evaluating the impact of therapeutic switching from human insulin to analogues, particularly in paediatric populations from low- and middle-income countries. AIM: The study aimed to retrospectively assess the effectiveness and safety of transitioning from human insulin to insulin analogs in Tunisian children with diabetes. METHODS: This retrospective descriptive study included children with type 1 diabetes who changed their insulin therapy protocol after at least one year of treatment with human insulin. Clinical, therapeutic, and glycaemic homeostasis parameters were assessed following the transition from human insulin (NPH + rapid-acting insulin) to the Basal-Bolus insulin analog- protocol. RESULTS: The study included 60 patients. Following the switch, all patients showed a significant reduction in mean fasting blood glucose levels (11.11 mmol/l vs. 8.62 mmol/l; p=0.024). Glycated haemoglobin A1C levels decreased notably in children who adhered to their diet (from 9.93% to 8.38%; p=0.06) and/or engaged in regular physical activity (from 10.40% to 8.61%; p=0.043). The average number of hypoglycemic events per year decreased from 4.03 events/year to 2.36 events/year (p=0.006), along with a decrease in the rate of patients hospitalized for acid-ketotic decompensation (from 27% to 10%; p=0.001). Financial constraints led to 82% of patients reusing microfine needles ≥2 times per day, and 12% were compelled to revert to the initial insulin therapy protocol due to a lack of access to self-financed microfine needles or discontinued social coverage. CONCLUSIONS: Although insulin analogues offer clear benefits, their use poses challenges as a therapeutic choice for children with diabetes in low- to middle-income countries. These challenges hinder the achievement of optimal glycemic control goals.

Comparison of long-term anti-RBD SARS-CoV-2 antibody response following different vaccination schemes in Tunisia.

AIM: The study aimed to compare long-term vaccine-induced humoral immunity following different vaccines regimens. METHODS: Anti-S-RBD total antibody levels were measured in blood samples of 167 participants nearly 6 months post-vaccination. Participants had received one; two or four doses of Pfizer vaccine or who received a third dose of mRNA vaccine (Pfizer) and primed with mRNA (Pfizer/Moderna), adenoviral (AstraZeneca/Jonson & Jonson) or inactivated (CoronaVac/Sinopharm) vaccine. RESULTS: Among all vaccination regimens, fourth dose of Pfizer achieved the highest S-RBD antibody titers. Nevertheless, the third dose of mRNA vaccine primed with adenoviral vaccine achieved the lowest titers of S-RBD antibody. Notably, the group that received a third dose of mRNA primed with two doses of mRNA vaccine exhibited higher S-RBD antibody compared to groups inoculated with a third dose of mRNA and primed with inactivated or adenovirus vaccine. CONCLUSION: Our data showed the superiority of three mRNA vaccinations compared to third heterologous vaccine (inactivated of adenoviral) including mRNA as booster in terms of humoral immunogenicity. Our findings supporting the use of additional booster shot from a more potent vaccine type such as mRNA vaccines. Nevertheless, due to the limited number of subjects, it is difficult to extrapolate the results of our study to the whole of Tunisian population. Future studies should investigate a larger cohort and other potential correlates of protection, such as cellular immunity and how it is affected by different vaccination schemes after long-term post-vaccination.

Sarcopenia prevalence and risk factors in obese Tunisian adults.

INTRODUCTION: Sarcopenia is a clinical condition defined as low skeletal muscle mass and function. It has been identified and described as a geriatric syndrome, but it may arise in individuals with obesity at any age. AIM: screen for sarcopenia in obese adults and identify the nutritional, clinical and biological risk factors associated with the development of sarcopenic obesity (SO+). METHODS: Descriptive cross-sectional study, including 53 obese patients. Screening for sarcopenia has been established according to pathological thresholds proposed by the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO). RESULTS: Mean age was 44.34±13.51 years. Prevalence of Sarcopenia was 7.5% (SO+). The average intakes of calorie, lipids and saturated fatty acids were higher in SO+. A statistically significant relationship was found between low skeletal muscle mass (SMM/W) and the average intake of vitamin PP (p=0.014) and vitamin B9 (p=0.009). Mean BMI (45.86 kg/m² for SO+ versus 39.29 kg/m² for SO-; p=0.03) and mean visceral fat (16.55 l for SO+, versus 10.93 l for SO-; p=0.043) were significantly higher in SO+. A statistically significant relationship was found between insulin resistance and low (SMM/W), as attested by mean insulinemia (28.81 µIU/mL for low SMM/W, versus 14.48 µIU/mL for normal SMM/W; p=0.004) and HOMA index (7.94 for low SMM/W, versus 3.49 for normal SMM/W; p=0.002), which were higher in cases of low (SMM/W). CONCLUSION: We recommend promoting a balanced, low-energy-density diet to improve insulin sensibility and thus reduce the risk of sarcopenia. Regular physical activity is also strongly recommended.

Urinary tract infections in chronic kidney disease in Nephrology unit, University Hospital Center of Befelatanana, Antananarivo.

INTRODUCTION: Urinary tract infection is the leading cause of nosocomial infection worldwide. It is a factor in the progression of chronic kidney disease. AIM: To determine the epidemiological, clinical, microbiological, therapeutic and evolving profile of patients with chronic kidney disease and urinary tract infection. METHODS: This was a retrospective, descriptive study lasting 5 years, from January 2014 to december 2018 in chronic kidney disease with urinary tract infection. RESULTS: Fifty-one patients (7.15%) were retained with a mean age of 53.03 years and a sex ratio of 0.55. Chronic kidney disease was in end-stage in 45.1% (n=23). Cystitis was found in 49.02% (n=25) and gram-negative bacilli were found in 74.50% (n=38), predominantly Escherichia coli (54.90%). Third generation of cephalosporins and fluoroquinolones were frequently prescribed as probabilistic antibiotics. Resistance to beta-lactam antibiotics was 50% for Escherichia coli. Factors influencing severe infection were: advanced age, male gender, urinary lithiasis, multiple antibiotic resistance and non-enterobacterial germs. CONCLUSION: Urinary tract infection in chronic kidney disease were frequent and particularly severe.

Malaria screening: what is the contribution of molecular biology?

INTRODUCTION: According to the World Health Organization, Microscopy is the gold standard for diagnosing malaria. However, the performance of this examination depends on the experience of the microscopist and the level of parasitemia. Thus, molecular biology detection of malaria could be an alternative technique. AIM: evaluate the contribution of molecular biology in detecting imported malaria. METHODS: This was a descriptive, prospective study, including all students, from the Monastir region, and foreigners, from countries endemic to malaria. The study period was from September 2020 to April 2021. Each subject was screened for malaria by three methods: direct microscopic detection of Plasmodium, detection of plasmodial antigens, and detection of plasmodial DNA by nested PCR. RESULTS: Among the 127 subjects screened, only one had a positive microscopic examination for Plasmodium falciparum. Among the 126 subjects with a negative microscopic examination, twelve students had a positive nested PCR result, i.e. 9.5%. Molecular sequencing allowed the identification of ten isolates of Plasmodium falciparum, one Plasmodium malariae and one Plasmodium ovale. Our study showed that the results of nested PCR agreed with those of microscopy in 90.6% of cases. CONCLUSION: Nested PCR seems more sensitive for the detection of low parasitemias. Hence the importance of including molecular biology as a malaria screening tool to ensure better detection of imported cases.

Clinical and genetic spectrum of Ataxia Telangiectasia Tunisian patients: Bioinformatic analysis unveil mechanisms of ATM variants pathogenicity.

Ataxia Telangiectasia (AT) is a rare multisystemic neurodegenerative disease caused by biallelic mutations in the ATM gene. Few clinical studies on AT disease have been conducted in Tunisia, however, the mutational landscape is still undefined. Our aim is to determine the clinical and genetic spectrum of AT Tunisian patients and to explore the potential underlying mechanism of variant pathogenicity. Sanger sequencing was performed for nine AT patients. A comprehensive computational analysis was conducted to evaluate the possible pathogenic effect of ATM identified variants. Genetic screening of ATM gene has identified nine different variants from which six have not been previously reported. In silico analysis has predicted a pathogenic effect of identified mutations. This was corroborated by a structural bioinformatics study based on molecular modeling and docking for novel missense mutations. Our findings suggest a profound impact of identified mutations not only on the ATM protein stability, but also on the ATM-ligand interactions. Our study characterizes the mutational landscape of AT Tunisian patients which will allow to set up genetic counseling and prenatal diagnosis for families at risk and expand the spectrum of ATM variants worldwide. Furthermore, understanding the mechanism that underpin variant pathogenicity could provide further insights into disease pathogenesis.

Short-term effects of announcing spirometric lung-age on smokers' attitudes: results from a Tunisian real-life pilot study.

BACKGROUND: To determine the effects of informing smokers of their spirometric lung-age (SLA) on smoking cessation (SC) rates and tobacco consumption. RESEARCH DESIGN AND METHODS: An interventional study was conducted in real-life through a humanitarian event led by the Red Crescent on 9 January 2022, in Hammam-Sousse (Sousse, Tunisia). The study comprised four steps: i) Medical questionnaire (general questionnaire, Fagerström test for cigarette dependence, SC motivation questionnaire); ii) Measurement of spirometric data; iii) SLA estimation and its announcement to participants; and iv) Self-reported evaluation of smoking behavior three months later through telephonic recall. Smokers were divided into groups (nondependent vs. dependent groups and insufficient/moderate motivation vs. high/very high motivation groups) and categories (ceased smoking, reduced consumption, maintained stable or increased consumption). RESULTS: Fifty-two smokers were included (94% were males). Three months after the event, i) 9 (17%) smokers ceased smoking, ii) 39 (75%) smokers reduced their daily smoking consumption by 12 ± 8 cigarettes/day, and iii) 4 (8%) smokers maintained stable (n = 3) or increased (n = 1) consumption. CONCLUSIONS: Informing smokers of their SLA led 92% of them to cease smoking or reduce their consumption. Announcing SLA could be an effective motivational tool and an easy-to-understand concept to help smokers cease their habit.